How is shannon and weaver's model an improvement on lasswell's formula?

Answer 1

It was not so much an improvement as another perspective on the same question. In the 1940s, a number of scholars began to focus their attention on the study of Mass Communication (which until then had generally been ignored by academia), as well as doing more analysis on how communication occurred between friends, in groups, at work, etc. Harold Lasswell created his theory in 1948: he reduced the process of communication to how the message was transmitted: "who says what to whom, via what channel, and to what effect?" In other words, who (the sender) says what (the message) to whom (the receiver), via what channel (the word "channel" does not mean a TV channel-- it means the medium or manner in which the communication has occurred, such as by voice, by telephone, by a sign or signal, by writing a letter, etc), and to what effect (what was the purpose of the message, and did it produce the effect the sender hoped for).

Then, in 1949, Claude Shannon and Warren Weaver produced a somewhat simpler mapping of how communication occurs-- it too focused on transmission: The SRC theory, where S was the source or the sender of the message, R was the receiver, and C was the channel (or by what means the message was sent). The problem with both of these theories was they did not take into account a person's culture or socialization or gender or age or the context under which the communication was attempted. It treated all senders and receivers as isolated individuals and tried to come up with an all-purpose formula for describing communication. Still, these two theories were important because they were the beginning of what became a growing and influential field of study that to this day is producing some very interesting theories and ideas about the way humans (and also animals) communicate.